Assessment of non-prismatic beams having symmetrical parabolic haunches with constant haunch length ratio of 0.5

No Thumbnail Available

Date

2012

Journal Title

Journal ISSN

Volume Title

Publisher

TECHNO-PRESS

Access Rights

info:eu-repo/semantics/closedAccess

Abstract

Single span historic bridges often contain non-prismatic members identified with a varying depth along their span lengths. Commonly, the symmetric parabolic height variations having the constant haunch length ratio of 0.5 have been selected to lower the stresses at the high bending moment points and to maintain the deflections within the acceptable limits. Due to their non-prismatic geometrical configuration, their assessment, particularly the computation of fixed-end horizontal forces (FEFs) and fixed-end moments (FEMs) becomes a complex problem. Therefore, this study aimed to investigate the behavior of non-prismatic beams with symmetrical parabolic haunches (NBSPH) having the constant haunch length ratio of 0.5 using finite element analyses (FEA). FEFs and FEMs due to vertical loadings as well as the stiffness coefficients and the carry-over factors were computed through a comprehensive parametric study using FEA. It was demonstrated that the conventional methods using frame elements can lead to significant errors, and the deviations can reach to unacceptable levels for these types of structures. Despite the robustness of FEA, the generation of FEFs and FEMs using the nodal outputs of the detailed finite element mesh still remains an intricate task. Therefore, this study advances to propose effective formulas and dimensionless estimation coefficients to predict the FEFs, FEMs, stiffness coefficients and carry-over factors with reasonable accuracy for the analysis and re-evaluation of the NBSPH. Using the proposed approach, the fixed-end reactions due to vertical loads, and also the stiffness coefficients and the carry-over factors of the NBSPH can be determined without necessitating the detailed FEA.

Description

Keywords

historic bridge, non-prismatic member, finite element analysis, parabolic haunch, stiffness factor, fixed-end reactions

Journal or Series

STRUCTURAL ENGINEERING AND MECHANICS

WoS Q Value

Q3

Scopus Q Value

Q2

Volume

42

Issue

6

Citation